Topband: Any Linrad selective limiter noise blanker experts here?
Jim Brown
jim at audiosystemsgroup.com
Tue Jan 21 13:30:05 EST 2020
On 1/20/2020 2:28 PM, Richard (Rick) Karlquist wrote:
> In most cases, line noise is a repeating function with a frequency of
> 50 or 60 Hz. To make an effective noise blanker in a contest, you
> simply have to make a filter that only responds to harmonics of the
> line frequency and then generate the inverse function from a 50 or
> 60 Hz line clock.
Unfortunately, that's too simple. For effective cancellation, that
inverse function must be precisely in phase (degrees, not polarity) and
equal in amplitude at each harmonic frequency.
73, Jim K9YC
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